Chapter 21, Problem 1FTE

Explanation of Solution

Program purpose:

The given program is for implementing stack using an array.

Compile-time error:

An error which occurs on the source code of a program when user violate the rules of writing syntax are called as compile-time error. If the code fails to prove its language syntax format, then the compiler will throw an error.

Error in the given code:

The flow of execution never reaches the statement top--; The execution of code will never reach the line written after the return statement. So the top--; should give before return statement to get affected.

Correct statement:

//Decrementing the value of top by 1

top--;

//returning the value at position top-1 in the stack

return s[top];

Corrected code:

/*An array implementation of a stack

function for popping a value from the stack.*/

int pop()

{

/*checks whether the value of top is equal to zero*/

        if (top == 0)

/*if the value of top is equal to zero function throws an exception to indicate the stack is empty*/

            throw new EmptyStackException( );

...